Using double reel tank for development

[bwidjaja]

Is there any special considerations needed when developing 2 120 reels at a time using a larger tank like the one linked below? I have only used a single reel tank to develop 1 roll of 120 film at a time.

Appreciate the insights.
http://www.freestylephoto.biz/9130-Arista-Stainless-Steel-Tank-30-oz.-With-SS-Top

 

[pschauss]

Theoretically you could have a disparity in development between the roll on the top and the one on the bottom especially if your processing times are short based on the time that it takes to pour the developer in and out. The reel on the bottom gets more time as you are pouring developer in and the one on the top gets more time when you are pouring out. As a practical matter, however, I have never found it to be a problem.

 

[Dan Daniel]

It takes a little longer for the liquid to redistribute when agitating. I will invert the tank and wait an extra half second or more before flipping upright than I would with a single reel tank. Without the small pause I am more prone to get edge unevenness with double reel 120 tanks.

 

[KenR]

Plus one

Plus one

As noted above, everyone is concerned about excess agitation in these tanks. I have been using metal and plastic tanks for many years without problems, but generally try to match the size of the tank to the number of reels. I am concerned about extra "dead space" causing excessive agitation. Therefore I have several different sized tanks and limit the dead space to only one reel. So in your situation, I would not develop 2 reels in a 4 reel tank. I would either wait until I have another roll or 2 of film that need development and do them all together, or get another smaller tank to take care of my 1 and 2 reel developing sessions.